Flox is structural.

Cabosil and micro baloons are not.

 

Flox (cotton FIBERS and epoxy) strengthen an epoxy joint because of the fibers in the matrix.

 

Cabosil and micro are cosmetic only and strengthen nothing. These components are weak themselves.  Cabosil keeps epoxy from running.  Micro make the fill light - but not strong.

 

Epoxy, by itself, is a brittle matrix.  Do not allow excess to make a structural joint unnecessarily brittle.

 

Don't experiment with these concepts.  If you are doing something structural, don't use cabosil or micro unless the use is as a fillet, to make later applications of bid (glass or carbon) to an L shaped joint across such a fillet, not at a sharp angle.  Flox is good for structural fillet material if the glass (or carbon) is to be applied whilst the flox is still wet.